#define _GNU_SOURCE | |
#include <stdio.h> | |
#include <stdlib.h> | |
char* ecvt(double x, int n, int* dp, int* sign) { | |
static char buf[16]; | |
char tmp[32]; | |
int i, j; | |
if (n - 1U > 15) | |
n = 15; | |
sprintf(tmp, "%.*e", n - 1, x); | |
i = *sign = (tmp[0] == '-'); | |
for (j = 0; tmp[i] != 'e'; j += (tmp[i++] != '.')) | |
buf[j] = tmp[i]; | |
buf[j] = 0; | |
*dp = atoi(tmp + i + 1) + 1; | |
return buf; | |
} |